Arctic Plants: Geographical Distribution 



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However, several of these are introduced weeds, for instance, Ervum, 

 Medicago, Trifolium, and Vicia in Greenland, where Lathyrus maritimus is the 

 only indigenous member of the family. The remarkably scant representation 

 of the family in the arctic region may indicate that the Papilionaceae are not 

 weU adapted to the severity of that climate. With regard to the circumpolar 

 Astragalus alpinus, Phaca frigida, and Oxytropis campestris, these have undoubt- 

 edly had their original centre in the polar regions; they are, together with Hedy- 

 sarum obscurum, Oxytropis lapponica, and Astragalus oroboides, the only ones 

 that have reached the Alps and the Pyrenees, _and it is interesting to notice that 

 while Hedysarum does occur in the arctic region of Europe and Asia, Oxytropis 

 lapponica and Astragalus oroboides are arctic in Scandinavia and Russia alone; 



